First footprints of ancient crocodile found in Sacheon

The footprints of an ancient crocodile that was large and walked on two legs from the Mesozoic period were discovered for the first time in the world in South Korea. Skeleton fossils of a small crocodile suspected to have walked on two legs were found before in the U.S., but the footprints are the first piece of solid evidence.

Kim Kyeong-soo, a professor of the Science Education Department at Chinju National University of Education, Bae Seul-mi, a researcher at the Korea Geoheritage Research Institute, and Lim Jong-deok, the head of the restoration technology laboratory at the National Research Institute of Cultural Heritage, have discovered the footprints of a large crocodile that walked on two feet on the early Cretaceous Jinju formation 110 million years ago in Jahye-ri, Sacheon, South Gyeongsang Province, along with the team of University of Colorado in the U.S. and University of Queensland in Australia. Their findings were published by the international journal Scientific Reports on Friday.

The research team found hundreds of footprint fossils of a reptile in Jahye-ri early last year. The fossils of its 18 to 24-centimeter-long feet clearly show the structure of soles, as well as the shape of toes. Based on the fact that it had four toes, the team first began research with an assumption that the reptile was a pterosaur from the Mesozoic period.

Research results demonstrate that the crocodile was up to three meters and had an interesting gait of walking on the two back legs while the tail and front legs were lifted in the air and the body was held up horizontal to the ground. Unlike the contemporary crocodiles that walk as if crawling with the legs pushing out to each side, the prehistoric crocodiles are presumed to have walked on their legs shooting out to the ground.

The Jinju formation where the new fossils were found is spread across Jinju, Sacheon, and Goseong in South Gyeongsang Province. “The Jinju formation is the world’s best source of diverse fossils that have been preserved well, even to the point of preserving the skin,” said Professor Lockley who has visited the region since the 1980s.


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